CVE-2026-23555
Published: March 23, 2026· Updated: Mar 23, 2026
Official Description
Any guest issuing a Xenstore command accessing a node using the
(illegal) node path "/local/domain/", will crash xenstored due to a
clobbered error indicator in xenstored when verifying the node path.
Note that the crash is forced via a failing assert() statement in
xenstored. In case xenstored is being built with NDEBUG #defined,
an unprivileged guest trying to access the node path "/local/domain/"
will result in it no longer being serviced by xenstored, other guests
(including dom0) will still be serviced, but xenstored will use up
all cpu time it can get.
Technical Analysis
CVE-2026-23555 requires local access, meaning attackers must already have a foothold on the target system.
The vulnerability requires no privileges and no user interaction, making it a prime target for automated exploitation campaigns and worm-like propagation.
A successful exploit results in availability disruption (denial of service), with a CVSS base score of 7.1.
The vulnerability has a "Changed" scope, meaning successful exploitation can impact components beyond the vulnerable component itself — such as the host operating system or adjacent services.
CVSS v3.1 Vector Breakdown
Exploit & PoC Resources
All References (3)
Quick Facts
Recommended Actions
- →Apply vendor patches immediately
- →Monitor CVE-2026-23555 in threat intel feeds
- →Review IDS/IPS signatures for exploitation attempts